    :next-image
    (fn [db [_ img-tag]]
      (-> db
+         (assoc :waiting false)
          (update-in [:url-list] rest)
          (update-in [:comic-imgs] conj img-tag)))))

  (rf/register-handler
   :scroll
   (fn [db _]
     (if (= (:page db)
            :read)
       (let [scroll-y (.-scrollY js/window)
             window-height (.-innerHeight js/window)
             screen-bottom (+ scroll-y window-height)

                       {:keys [chapter]} :location
                       :as db}]
  (api/get-img-tag site (first url-list))
  (let [{:keys [url-list] :as db} (assoc db
                                         :url-list (next url-list)
                                         :waiting true)
        new-location (assoc location :chapter
                            (inc
                             (read-string chapter)))]
